gsm basic 3

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Air Interface

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Air Interface

Radio Transmission Techniques

FDMA

TDMACDMA

Channels

Physical channelsLogical channels

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FDMA

Time

Frequency

Channel

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TDMA

Time

Frequency

0 1 2 3 4 5 6 7

Channel

Time Slot

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CDMAFrequency

Time

Code

Code 1

Code 2

Code 3

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Channels

Physical Channels

Associated with frequency bands, time slots, codes

Physical channels transfer bits from one network element

to another

Logical Channels

Distinguished by the nature of carried information and the

way to assemble bits into data units

Three types one-to-one: traffic channels between a BTS and a MS

one-to-many: synchronization signals from BTS to MSs in a cell

many-to-one: from MSs to the same BTS

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Air Interface Layers

Radio

Transmission

Logical

Channels

Messages

Radio

Transmission

Logical

Channels

Messages

Terminal BaseStation

Layer 1Bits

Layer 2

Packets

Layer 3

Messages

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GSM Frame Structure

3 57 26 57 8.251 1 3

0 7

...

...Superframe6.12 sec

120 msec

4.615 msec

0.57692 msec156.25 bits

51 Multiframe

26 Frames

8 Multiframe

Coded data Midamble

Tail bit Stealing Flag Guard period

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There are two types of multiframe

26 TDMA-frame multiframe is used to carry

TCH, SACCH and FACCH


BCCH, CCH, SDCCH and SACCH

Frame Types

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Burst and Frames

The information contained in one time slot

on the TDMA frame is call a burst.

Five types of burstNormal Burst (NB)

Frequency Correction Burst (FB)

Synchronization Burst (SB)Access Burst (AB)

Dummy Burst

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Trafficchannels(TCH)

Signaling

channel

TCH/F: Full-rate Traffic Channel

TCH/H: Half-rate Traffic Channel

FCCH: Frequency correction

SCH: SynchronizationBCCH: Broadcast control

PCH: Paging

AGCH: Access grant

RACH: Random access

SDCCH: Stand-alone dedicated control

SACCH: Slow associated control

FACCH: Fast associated control

Two-way

Base-to-

mobile

Two-way

Logical Channel List

BCH

CCCH

DCCH

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Logical Channels

Control Channels

Broadcast Channels (BCH)

Common Control Channels (CCCH)

Dedicated Control Channels (DCCH)

Traffic Channels (TCH)

Full Rate (TCH/F)

Half Rate (TCH/H)

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UP / Down-Link

Down-link: the transmission path from Base

Station to Mobile Station

Up-link: the transmission path from MobileStation to Base Station

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Control Channels

Broadcast Channels (BCH) Frequency Correction Channel (FCCH)

Synchronization Channel (SCH)

Broadcast Control Channel (BCCH)

Common Control Channels (CCCH) Paging Channel (PCH)

Random Access Channel (RACH)

Access Grant Channel (AGCH)

Dedicated Control Channels (DCCH) Stand alone Dedicated Control Channel (SDCCH) Cell Broadcast Channel (CBCH)

Slow Associated Control Channel (SACCH)

Fast Associated Control Channel (FACCH)

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Message name Transmitted by

AUTHENTICATION REQUEST

AUTHENTICATION RESPONSE

AUTHENTICATION REJECT

IDENTITY REQUEST

IDENTITY RESPONSETSMI REALLOCATION COMMAND

LOCATION UPDATING REQUET

LOCATION UPDATING ACCEPT

LOCATION UPDATING REJECT

IMSI DETACH REQUEST

CM SERVICE REQUEST

CM RE-ESTABLISHMENT REQUEST

MM-STATUS

Base

Mobile

Base

Base

MobileBase

Mobile

Base

Base

Mobile

Mobile

Mobile

Mobile/Base

Mobility Management Messages

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Message name

Starting a call

Transmitted by

SETUP

EMERGENCY SETUP

CALL PROCEEDING

PROGRESS

CALL CONFIRMED

ALERTING

CONNECT

Mobile/base

mobile

base

base

mobile

mobile/base

mobile/baseDuring a call

START DTMF

STOP DTMF

MODIFY

USER INFORMATION

Mobile

mobile

mobile/base

mobile/baseEnding a call

DISCONNECTRELEASE

RELEASE COMPLET

Mobile/basemobile/base

mobile/base

Abnormal conditions

STATUS

STATUS ENQUIRY

CONGESTION CONROL

Mobile/base

mobile/base

mobile/base

Call management messages

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Message name Logical channel Transmitted by

SYNC CHANNEL INFORMATION

SYSTEM INFORMATION (TYPE 1,2,3,4,5)

SYSTEM INFORMATION (TYPE 6)CHANNEL REQUESTPAGING REQUEST (TYPE 1,2.3)

IMMEDIATE ASSIGNMENTIMMEDIATE ASSIGNMENT EXTENDED

IMMEDIATE ASSIGNMENT REJECTASSIGNMENT COMMANDADDITIONAL ASSIGNMENT

PAGING RESPONSEMERSUREMENT REPORT

HANDOVER COMMANDHANDOVER ACCESS

PHYSICAL INFORMATIONHANDOVER COMPLETE

CIPHERING MODECHANNEL RELEASE

PARTIAL RELEASEFREQUENCY REDEFINITION

CLASSMARK CHANGE

CHANNEL MODE MODIFYRR STATUS

SCH

BCCH

SACCHRACHPCH

AGCHAGCH

AGCHFACCHFACCH

SDCCHSACCH

FACCHTCH

FACCHFACCH

FACCHFACCH

FACCHSACCHFACCH

SACCHFACCH

FACCHFACCH

SACCH

Base

Base

BaseMobileBase

BaseBase

BaseBaseBase

MobileMobile

BaseMobile

BaseMobile

BaseBase

BaseBase

Mobile

BaseMobile/base

Radio Resources Management Messages

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Prior

MSC

Prior

VLR HLR

Serving

VLR

Serving

MSC

Serving

BaseRegistration info

Store info

REGISTRATION NOTIFICATION INVOKE

Store info

Store info

Change info

remove info


REGISTRATION NOTIFICATION RESULT


REGISTRATION CANCELLATION INVOKE

remove info

REGISTRATION CANCELLATION RESULT


REGISTRATION CANCELLATION RESULTQUALIFICATION REQUEST INVOKE

QUALIFICATION REQUEST RESULT

PROFILE REQUEST INVOKE

PROFILE REQUEST RESULT

Message sequence and system operations for registration

of a terminal in a visited service area

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Mobilestation Basestation CategoryLogicalChannel


Carrier sine wave

SYSTEM INFORMATION TYPE3

CHANNEL REQUEST

IMMEDIATE ASSIGNMENT

LOCATION UPDATING REQUEST


CIPHERING MODE COMMAND

CIPHERING MODE ACK


TMSI ALLOCATION COMPLETE


CHANNEL RELEASE

RRM

RRM

RRM

RRM

MM

MM

MM

MM

MM

RRMRRM

RRM

FCCH

SCH

BCCH

RACH

AGCH

SDCCH

SDCCHSDCCH

SDCCHSDCCH

SDCCH

SDCCH

SDCCH

Location-Updating Procedure

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Mobilestation

Basestation

Category LogicalChannel

RRM

RRMRRM

RRM

RRM

RRM

MM

MM

RRMRRM

CMCM

CM

CM

RRM

RRM

CM

CM

CM

CM

RRM

FCCH

SCH

BCCHPCH

RACH

AGCH

SDCCH

SDCCH

SDCCH

SDCCHSDCCH

SDCCH

SDCCH

SDCCH

SDCCH

SDCCH

SDCCHFACCH

TCH

TCH

FACCH

FACCH

FACCH

FACCH

Carrier sine wave


SYSTEM INFORMATIONPAGING REQUEST

CHANNEL REQUEST


PAGING RESPONSE



CIPHERING MODECIPHERING MODE ACK

SETUP

CALL CONFIRMED

ALERTING

CONNECT

ASSIGNMENT COMMAND

ASSIGNMENT ACKCONNECT ACK

conversation

conversation

conversation

DISCONNECT

RELEASE

RELEASE COMPLETECHANNEL RELEASE

Call Deliver to MH

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Mobile-Assisted Handover

Mobilestation

Basestation

LogicalChannel

TCHTCHSACCHTCHTCH

TCHSACCH

TCHFACCHnew TCHTCH

TCHTCH

FACCH

TCHTCHSACCHTCH

TCHTCH

SACCH

TCH

conversation

conversation

MEASUREMENT REPORT

conversation

conversation

conversation

MEASUREMENT REPORT

conversation

HANDOVER COMMAND

HANDOVER ACCESS

HANDOVER ACCESS

HANDOVER ACCESS

PHYSICAL INFORMATION

HANDOVER COMPLETE

conversation

conversation

MEASUREMENT REPORT

conversation

conversation

conversation

MEASUREMENT REPORT

conversation

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Broadcast Channels (BCH)

To help the MH (Mobile Handset) measures

to turn to a BTS

to listen for the cell information to start roaming, waiting for calls to arrive, making

calls

Because BTSs are not synchronized with each

other, every time a MH decides to camp toanother cell, its FCCH, SCH, and BCCH must

be read.

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Frequency Correction Channel

(FCCH) Provide MH with the frequency reference of

the system

To enable the Mobile Handset (MH) tosynchronize with the frequency

Transmission properties

Transmit on the down-linkPoint to multi-point.

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Synchronization Channel (SCH)

MH synchronize with the structure within the

locative cell MH can receive information from the proper time slots

on the TDMA structure To ensure a GSM BTS is chose

The Base Station Identity Code (BSIC) can only bedecoded by a GSM BTS

Transmission properties Transmit on down-link

Point to multi-point.

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Broadcast Control Channel(BCCH)

BTS broadcast cell information to MHLAI ( Location Area Identity), to start roaming,

waiting for calls to arrive, making calls

maximum output power allowed in the cellinformation about BCCH carriers for the

neighboring cells MH will perform measurement to BTS

Transmission propertiesTransmit on down-link

Point to multi-point

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Common Control Channels

(CCCH) CCCH support the establishment of adedicated communication path (dedicated

channel) between the MH and the BTS

Three types of CCCH

Paging Channel (PCH)



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Paging Channel (PCH)

Used by BTS to page particular MH in the cellMH actively listen to PCH to check contact info

within certain time

Contact could be incoming call or short message

Contact info on PCH include IMSI (MHs identity number), or

TMSI (temporary number)

Transmission propertiesTransmit on down-link

point to point

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Used by MH to request a dedicated channel

for call setup

Shared by any MH attempts to access thenetwork

Channel request message contains the reason

for the access attempt


Transmit on up-link

Point to pint.

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The network assigns a signaling channel via

AGCH

A Stand alone Dedicated Control Channel(SDCCH) is assigned


Transmit on down-linkPoint to point

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Dedicated Control Channels

(DCCH) DCCH are used for transferring nonuserinformation between the network and the MH Messages on DCCH Including

channel maintenance mobility management

radio resource management

Four kinds of DCCH Stand alone Dedicated Control Channel (SDCCH)

Cell Broadcast Channel (CBCH)

Slow Associated Control Channel (SACCH)

Fast Associated Control Channel (FACCH)

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Stand alone Dedicated Control

Channel (SDCCH) Transfer signaling information between the

BTS and the MH

Typically used for location updating prior touse of a traffic channel


Bidirectional channel, transmit on both up anddown-link

Point to point.

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Cell Broadcast Channel (CBCH)

To carry Short Message Service Cell

Broadcast (SMSCB)

Use the same physical channel as SDCCH


Transmit on down-link

Point to multi-point

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Slow Associated Control Channel

(SACCH) Carries control and measurement parameters alongwith routine data necessary to maintain a radio

link between the MH and the BTS

On the uplink, MS sends averaged measurements(signal strength and quality) of current and neighboringBCCH

On downlink, MS receives information abouttransmitting power to use and an instruction with time

advance/retard

Transmission properties Bidirection channel, transmit on both up and down link

Point to point

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Fast Associated Control Channel

(FACCH) An FACCH is used over a TCH where it

steals time slots from a TCH

a 20 ms segment of speech is stolen to carryhandover signaling information

Appears on demand

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Traffic Channels (TCH)

TCH transport user information (speech/data)

TCH are bidirectional dedicated channels

between the network and the MH

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Mobilestation Basestation Category

Logical

Channel


Carrier sine wave

SYSTEM INFORMATION TYPE3

CHANNEL REQUEST


LOCATION UPDATING REQUEST


CIPHERING MODE COMMAND

CIPHERING MODE ACK


TMSI ALLOCATION COMPLETE


CHANNEL RELEASE

RRM

RRM

RRM

RRM

MM

MM

MM

MM

MM

RRMRRM

RRM

FCCH

SCH

BCCH

RACHAGCH

SDCCH

SDCCHSDCCH

SDCCHSDCCH

SDCCH

SDCCH

SDCCH

Location-Updating Procedure

Call Deliver to MH

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Mobilestation

Basestation

Category LogicalChannel

RRM

RRMRRM

RRM

RRM

RRM

MM

MM

RRMRRM

CMCM

CM

CM

RRM

RRM

CM

CM

CM

CM

RRM

FCCH

SCH

BCCHPCH

RACH

AGCH

SDCCH

SDCCH

SDCCH

SDCCHSDCCH

SDCCH

SDCCH

SDCCH

SDCCH

SDCCH

SDCCHFACCH

TCH

TCH

FACCH

FACCH

FACCH

FACCH

Carrier sine wave


SYSTEM INFORMATIONPAGING REQUEST

CHANNEL REQUEST


PAGING RESPONSE



CIPHERING MODECIPHERING MODE ACK

SETUP

CALL CONFIRMED

ALERTING

CONNECT

ASSIGNMENT COMMAND

ASSIGNMENT ACKCONNECT ACK

conversation

conversation

conversation

DISCONNECT

RELEASE

RELEASE COMPLETECHANNEL RELEASE

Call Deliver to MH

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Mobile-Assisted Handover

Mobilestation

Basestation

LogicalChannel

TCHTCHSACCHTCHTCH

TCHSACCH

TCH

FACCHnew TCHTCH

TCHTCH

FACCH

TCHTCHSACCHTCH

TCHTCH

SACCHTCH

conversation

conversation

MEASUREMENT REPORT

conversation

conversation

conversation

MEASUREMENT REPORT

conversation

HANDOVER COMMAND

HANDOVER ACCESS

HANDOVER ACCESS

HANDOVER ACCESS

PHYSICAL INFORMATION

HANDOVER COMPLETE

conversation

conversation

MEASUREMENT REPORT

conversation

conversation

conversation

MEASUREMENT REPORT

conversation

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Burst The information contained in one time slot is a

burst

Five types of burst Normal Burst (NB)

To carry information on traffic and control channels

Frequency Correction Burst (FB) To synchronize the frequency of the mobile

Synchronization Burst (SB) To synchronize the frames of the mobile

Access Burst (AB) For random and handover access

Dummy Burst For padding the frame

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Bursts and Frames

There are two types of multiframe


TCH, SACCH and FACCH51 TDMA-frame multiframe is used to carry

BCCH, CCH, SDCCH and SACCH

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Bursts and Frames

... 2047204620452044204310 2 3 4 5

...0 1 2 3 504948470 1 2524...

0 1 2524... 0 1 5049...

0 1 2 3 4 5 6 7

1 hyperframe = 2048 superframes = 2,715,648 TDMA frames (3 hours 28 minutes 53 seconds 760 microseconds)

1 superframe = 1326 TDMA frames (6.12 seconds)

= 51 (26-frame) multiframes or 26 (51-frame) multiframes

1TDMA frame = 8 timeslots

(120/26 =~ 4.615 ms)

1 (26-frame) multiframe

= 26 TDMA frames (120 ms)

1 (51-frame) multiframe

= 51 TDMA frames (120 ms)

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Bursts and Frames

0 1 2 3 4 5 6 7

GP

8.25

TB

3

Encrypted bits 57flag

1

Training sequence 26 flag

1

Encrypted bits 57TB

3

TB

3Fixed bits 142

GP

8.25

TB

3

GP

8.25

TB

3

TB

3Encrypted bits 39 Synchronization sequence 64 Encrypted bits 39

TB

3 Synchronization sequence41

Encrypted bits 36 TB3

GP 68.25

GP

8.25

TB

3TB

3Mixed bits 58 Training sequence 26 Mixed bits 58

Normal Burst (NB)

Frequency correction

burst (FB)

Synchronization

burst (SB)

Access burst (AB)

Dummy burst (DB)

TB: Tail bits

GP: Guard period

1 TDMA frame = 8 timeslots

1 timeslot = 156.25 bit durations (15/26 =~ 0.577 ms)

(1 bit duration 48/13 =~ 3.69 micro sec)

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Normal Burst

T3 Coded Data

57

Training

Sequence 26

Coded

Data 57

GP

8.25

S1 S1 T3

148 bits = 0.54612 msec

This burst is used to carry information on TCH and on the control channels

BCCH, PCH, AGCH, SDCCH, ASCCH and FACCH.

Note: GP (Guard Period)

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Random Access Burst

T8 Synchronization

sequence 41

Coded Data

36

Guard Period

68.25T3

88 bits = 0.32472 msec

68.25 bits = 0.252 msec which is equivalent to 75.5 km

propagation delay.

That is, the max. allowed distance between mobile station

and BTS is 37.75 km. Based on other system parameters,

the max cell size is 35 km in GSM.

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Logical Channels Characteristics

LogicalChannel

Uplink-only

Downlink-only

Both uplink& downlink

Point-to-pint

Broadcast Dedicated shared

BCCHFCCHSCHRACHPCHAGCHSDCCHSACCHFACCHTCH

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GSM Architecture

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GSM System Architecture

PSTN

Data Terminal

HLR/

VLR

MSCBSC

OMC(Operation & Maintenance

Center)

OperationTerminal

BTS

HandsetA

X.25

A-bis SS7

Network sub-system PSTNRadiosub-system

Mobile

station

UM

SIMcard

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GSM Network Elements

Handset

BTS: Base Transceiver Station

MSC: Mobile Switching Center BSC: Base Station Controller

HLR/VLR: Home Location Register/Visiting

Location Register SIM Card: Subscriber Identity Module Card

Service Centers: USSD, SMS, ...

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Mobile Handset (MH)

Used by the subscriber to access the GSM

network via the air interface

Contains the hardware and software specificto the radio interface

Need a Subscriber Identity Module (SIM)

which contains the subscriber-specific datato access GSM network, except emergency

call

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Base Transceiver Station (BTS)

/ Base Station Responsible for communication to and from MHsvia air interface

MH communicates with the mobile system using a

radio channel to a BTS BTS comprises radio transmission and reception

devices

Including the antennae and signaling processing

specific to the radio interface

BTS separates the speech and control signaling

associated with a MH and sends them to the BSC

on separate channels

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Mobile services Switching

Center (MSC) Responsible for all switching functionsrelated to call processing

Coordinate the setting up of calls to and from

GSM users

MSC is the interface between GSM network

& PSTN (Public Switched Telephone

Network)

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Base Station Controller (BSC)

Monitor and Control several base stationsFrequency administration, control of BTSs,

exchange functions

Responsible for all the radio interfacemanagementChannel allocation and release, handover

management

BSC is the interface between MSC and BTSBSC is connected on one side to several BTSs

and on the other side to the MSC

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Home Location Register (HLR)

A database in charge of the management of

mobile subscribers

Contains information of network subscribersInformation on teleservices and bearer services

subscription, service restrictions, and

supplementary services

The data stored in HLR is of a semipermanent

nature and does not usually change from call to

call

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Visitor Location Register (VLR)

Contains the relevant data of all MHs

currently located in a serving MSC

The permanent data is the same as data in the

HLR

The temporary data includes

Temporary Subscriber Identity (TMSI)

Location Area Identity (LAI) of an MH

VLR allocates mobile subscriber roaming

numbers (MSRNs) for the incoming call setup

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Subscriber Identity Module (SIM)

Subscriber Identity Module

Contains

phone number (MSISDN)

international mobile subscriber identity (IMSI)

status of SIM

service code

authentication key PIN (personal identification code)

PUK (personal unlock code)

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SIM Cards

SIM cards are embedded with a microprocessor

Stores customer identity information and is made tofit inside the cellular phone

Memory capacity1K, 3K, 8K, 16K

With/Without OTAC (Over The Air Customization)

Two types of SIM card form factorsID-1 SIM

Plug-In SIM

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Application Service Centers

Responsible for GSM network add-on servicesOperation and Maintenance Center (OMC)

Monitoring and control the network

Usually connect with MSC, BSC, HLR, and other servicecenters

Short Message Service Center (SMSC)

provide short message services

usually connect to MSC

Unstructured Supplementary Service Data Center(USSDC)

provide USSD service in the form of *ID*ID*info#

usually connect to HLR

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Geographical Network Structure

Location Units

Cell

Location Area (LA)

MSC/VLR Service Area

PLMN (Public Land Mobile Network) Service

Area

GSM Service Area

Cell Planning

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Location Information --GSM Service Area Hierarchy

The area in

which a

subscriber

can access

the

network.cell

Location Area

MSC/VLR

PLMN Service Area(one per operator)

GSM Service Area

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Cell Characteristics

The Basic Union In The System

defined as the area where radio coverage is

given by one base station.

Addressed by Cell Global Identity (CGI)

A cell has one or several frequencies,

depending on traffic load.

Frequencies are reused, but not used in

neighboring cells due to interference.

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Cell Planning

Reusing frequencies in

different geographic

areas:

7 cell repeat pattern istypical, but other

patterns are also

common

A3A1

A2G3

G1

G2C3

C1

C2

B3B1

B2

F3F1

F2

D3 D1D2

E3E1

E2

G3G1

G2

F3F1

F2

C3C1

C2

A3A1

A2B3

B1

B2

E3 E1E2

D3D1

D2

7-cell reuse

pattern

Frequency

reuse

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Cell Patterns

13

23

27

16

4

5

K=3K=7

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Frequency Utilization v.s. K

Frequency cant be reused in the same pattern

Larger K

More channels in a pattern

Higher subscriber number

Worse frequency reusability

Smaller K

Less channels in a pattern, high channel distortionSmaller subscriber number

Better frequency reusability

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Numbering & Routing

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Numbering

Mobile Subscriber ISDN Number (MSISDN)

Mapping to Mobile Station Roaming Number (MSRN)

by HLR

International Mobile Subscriber Identify (IMSI) Stored in SIM/HLR

Temporary Mobile Subscriber Identity (TMSI)

Assigned by VLR, Stored in VLR

International Mobile Equipment Identity (IMEI)

Unique ID to handset, used by air interface

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ID-Numbers

MSISDN = CC + NDC + SN

MSISDN: Mobile Station ISDN Number

CC Country Code

NDC National Destination Code

SN Subscriber Number

IMSI = MCC + MNC + MSIN

IMSI International Mobile Subscriber Identity MCC Mobile Country Code

MNC Mobile Network Code

MSIN Mobile Station Identification Number

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ID-Numbers (cont.)

IMEI = TAC + FAC + SNR + spare

IMEI Internal Mobile Equipment Identity

TAC Type Approval Code, determined by a centralGSM/PCS body

FAC Final Assembly Code, identifies themanufacturer

SNR Serial Number, uniquely identifies allequipment within each TAC and FAC

IMEISV = TAC + FAC + SNR + SVN IMEISV International Mobile Equipment Identity and

Software Version Number

SVN Software Version Number

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ID-Numbers (cont.)

MSRN = CC + NDC + SN

MSRN Mobile Station Roaming Number

CC Country Code

NDC National Destination Code SN Subscriber Number. In this case, the address to

the serving MSC

LAI = MCC + MNC + LAC

MCC Mobile Country Code

MNC Mobile Network Code

LAC Location Area Code

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ID-Numbers (cont.)

CGI = MCC + MNC + LAC + CI CGI Cell Global Identity

CI Cell Identity

BSIC = NCC + BCC

BSIC Base Station Identity Code NCC Network Color Code (3bits)

BCC Base Station Color Code (3bits)

LN = CC + NCD + LSP

LN Location Number CC Country Code

NCD National Destination Code

LSP Locally Significant Part

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ID -Numbers (cont.)

LN = CC + NCD + LSP

LN Location Number

CC Country Code

NCD National Destination Code LSP Locally Significant Part

RSZI = CC + NDC + ZC

RSZI Regional Subscription Zone Identity

CC Country Code

NDC National Destination Code

ZC length of the Zone code (2 octets)

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Routing

Information resident in MS & SIM

IMSI, TMSI, IMEI, and misc. information

Routing Information used by NetworkMSISDN, MSRN

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Location Registry

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Location Registry

Registration Message Flow

Inter-LA movement

In the same MSC

Inter-MSC movement

In the same GSM Operator

Inter-VLR movement

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Registration Message Flow-- Inter-LA Movement

1

23

4

HLR

MSC2

LA2LA1

MSC1

VLR2VLR1

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Registration Message Flow-- Inter-MSC Movement

1

2

3

4

5

6

LA2

MSC2

HLR

LA1

MSC1

VLR1VLR2

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HLR

VLR1VLR2

LA1 LA2

Registration Message Flow-- Inter-VLR Movement

1 6

78

3

2

45

MSC2MSC1


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PriorMSC

PriorVLR HLR

ServingVLR

ServingMSC

ServingBase

Registration infoStore info


Store info

Store info

Change info

remove info





remove info




QUALIFICATION REQUEST INVOKE

QUALIFICATION REQUEST RESULT

PROFILE REQUEST INVOKE

PROFILE REQUEST RESULT


of a terminal in a visited service area

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Call Setup

Mobile originated call mobile to land call flow (part 1 of 2)

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MS BSS MSC/VLR HLR PSTN

Channel REQuest

IMMediate ASSign

Complete layer 3 Info,

AUThentication REQuest

TMSI REALlocation CoMmanD

SETUP

Mobile-originated call, mobile to land call flow (part 1 of 2)

AUThentication RESponse

Cipher Mode Complete

Cipher Mode CMD

Cipher Mode CMD

Cipher Mode Complete

TMSI REALlocation COMplete

Mobile originated call mobile to land call flow (part 2 of 2)

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CALL PROCeeding

Mobile-originated call, mobile to land call flow (part 2 of 2)

Assignment Request

ASSignment CoMmanD

Assignment Complete

Assignment Complete

Initial Address Message (IAM)

Address Complete message (ACM)

AlertingAnswer Signal/answer Message(ANM)

connect

Connect Acknowledge

Call setup to a roaming subscriber

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Prior

MSCPrior

VLR HLR

Serving

VLR

Serving

MSCServing

Base

Receive callsetup request

LOCATION REQUEST INVOKE

ROUTE REQUEST INVOKE

ROUTE REQUEST INVOKE

ROUTE REQUEST RESULT

ROUTE REQUEST RESULT

LOCATION REQUEST RESULT

Call setup request

(temporary phone number) Page command

PAGE

Delete MIN

conversationVMPS call setup

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GMSC

MSC/VLR

BSC

HLR

BTS BTS BTS

MSISDN

MSISDN

MSRN

IMSI

MSISDN-->IMSI-->

MSC/VLR Service Area

IMSIMSRN

6.

1.3.

5.

4.

7.

8.

8. 9.

2.

PSTN5.

Call Delivery

Mobile terminated call land to mobile call flow (part 1 of 2)

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Mobile-terminated call, land to mobile call flow (part 1 of 2)

Send routing info.

Provide roaming number

Roaming numberRouting information

Initial address messagePaging command

Paging request

Channel request

Immediate assign

Complete layer 3 info.

Authentication request

Authentication response

Cipher mode cmdCipher mode cmd

Cipher mode cmdCipher mode complete

Mobile terminated call mobile to land call flow (part 2 of 2)

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Mobile-terminated call, mobile to land call flow (part 2 of 2)


TMSI reallocation commandTMSI reallocation complete

SETUP

Call confirmed

Assignment request

Assignment command

Assignment complete

Assignment complete

alerting

connect

Connect acknowledge

Address complete message

Answer signal /answer message

Call request athome MSC

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Example of call management scenarios

Fig. 4.5 Busy

indication

to caller

Action by

serving

MSC

Announcement

to caller

HLR sends call forwardingnumber to home MSC

Terminalidle andsubscriberresponds

Terminalbusy

No answeror no pageresponse

Unconditionalcall forwarding

home MSC

Callwaiting

Callforwarding

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Handover

Location update call flow

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MS BSS MSC VLR HLR VLR

Location Update in new MSC

Authenticate

Authentication Resp,

Start ciphering

Forward new TMSI

Loc.n area up. acc

Send para

(authentication)

Authentication Prar.

Update location

Insert subscriber data

Subs. Data Ins. Acc.Loc.n update acc

Cancel location

Loc.n cancellation acc.

Location update call flow

Inter-MSC handover

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Inter MSC handover

BSS1 MSC-A MSC-B BSS2 VLR-B

Handover request

MS

Perform handoverAllocate handover number

Handover request

Send handover report

Handover request ackRadio channel ack

Initial address messageAddress complete message

Handover command

Handover commandHandover access

Handover detect physical information

Handover complete

Handover completeAnswer signal

Send end signalClear command

Clear complete End signalRemove handover report

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HLR

VLR

GMSC

MSC

MSISDN

MSISDN

MSRN

MSRNIMSI

IMSI

MSRN

MSRN

1

2

3 45

6

The Use of MSRN

PSTN

gsm basic 3

Documents